is Br2(L)+Cl2(g)--->BrCl(g) a balanced equation?

Answer 1

No, but
Br2+Cl2---> 2BrCl
is balanced

Answer 2

yes

Answer 3

No two anions may be put together in an ionic compound. Cl and Br are both negatively charged. You could put BACl2 for example.

Answer 4

Br2+Cl2<-->2BCl